The provisions of § 8-3955 shall apply to all persons who transfer hereafter and to those who transferred from one retirement system to the other during the period from July 1, 1972, to June 4, 1975. Persons who transferred membership between retirement systems prior to July 1, 1972, shall have the option to retain all rights, benefits, and privileges under chapter 37 of this title as preserved under § 8-3935(4); or the option to have his or her rights, benefits, and privileges credited, calculated, and paid in accordance with the provisions, methods, and procedures provided in § 8-3955.